While playing the game press down on the d-pad then your picmin will come to you and pick you up and take you to their onion and you will come back up and then you should see some fireworks come out of the onion

Challenge Mode Option:Save then game and unlock the Challenge Mode option at the Main menu and replay previously completed sections In a time attack scenario and collect as many Pikmin as possible befoe nightfall.

Fireworks:Round up four Pikmin to carry you back to your base by pressing Down. Aquick fireworks display will then happen, the fireworks will also eventuallyhappen if you remain idle.